Ishimori Nana, Oguchi Jun, Nakazawa Yosuke, Kobata Kenji, Funakoshi-Tago Megumi, Tamura Hiroomi
a Faculty of Pharmacy , Keio University, Shibakoen , Minatoku , Tokyo , Japan.
b Faculty of Pharmaceutical Sciences , Josai University , Sakado , Saitama , Japan.
Curr Eye Res. 2017 Jun;42(6):864-870. doi: 10.1080/02713683.2016.1262877. Epub 2017 Jan 27.
Coffee is a widely consumed beverage. While recent studies have linked its intake to a reduced risk of cataracts, caffeine is believed to be the key factor for its effect. To know how roasting beans affects the effect of coffee on cataract formation, we investigated the impact roasting using a selenite-induced cataract rat model.
Sprague Dawley rats were given a single injection of sodium selenite, which induced formation of nuclear cataracts by day 6, with or without coffee intake (100% coffee, 0.2 mL/day) for following 3 days.
The concentrations of glutathione (GSH) and ascorbic acid (AsA) in selenite-induced cataract lenses declined to half that of controls. However, 3 days of coffee intake ameliorated the reduction of GSH and AsA so that concentrations remained at 70-80% that of controls. Roasting enhanced the preventive effect of coffee by further reducing cataract formation and ameliorating selenite-induced reduction of antioxidants. High-performance liquid chromatography analysis revealed degradation of chlorogenic acid and generation of pyrocatechol during the coffee roasting process. We discovered that pyrocatechol, at doses equivalent to that found in dark-roasted coffee, was equally effective as caffeine at reducing cataract formation and ameliorating the reduction of antioxidants.
Our results indicate that pyrocatechol, generated during the roasting process, acts as an antioxidant together with caffeine to prevent cataract formation.
咖啡是一种广泛饮用的饮品。虽然最近的研究将其摄入与降低白内障风险联系起来，但咖啡因被认为是其发挥作用的关键因素。为了了解烘焙咖啡豆如何影响咖啡对白内障形成的作用，我们使用亚硒酸钠诱导的白内障大鼠模型研究了烘焙的影响。
给Sprague Dawley大鼠单次注射亚硒酸钠，在第6天诱导核性白内障形成，之后3天给予或不给予咖啡摄入（100%咖啡，0.2 mL/天）。
亚硒酸钠诱导的白内障晶状体中谷胱甘肽（GSH）和抗坏血酸（AsA）的浓度降至对照组的一半。然而，3天的咖啡摄入改善了GSH和AsA的降低，使其浓度保持在对照组的70 - 80%。烘焙通过进一步减少白内障形成和改善亚硒酸钠诱导的抗氧化剂减少，增强了咖啡的预防作用。高效液相色谱分析显示，咖啡烘焙过程中绿原酸降解并生成邻苯二酚。我们发现，剂量与深烘焙咖啡中相当的邻苯二酚在减少白内障形成和改善抗氧化剂减少方面与咖啡因同样有效。
我们的结果表明，烘焙过程中产生的邻苯二酚与咖啡因一起作为抗氧化剂预防白内障形成。
